Spring-ai Fix Neo4jVectorStore max allowed dimension size to 4096

The Neo4j "vector-2.0" index provider allows up to 4096 dimensions.

@pivotal-cla This is an Obvious Fix

Issue #644

Comment From: tzolov

Thanks @vbartacek. I've modified the PR a bit to remove the upper boundary.

Comment From: tzolov

Rebased, modified to remove the upper dimension boundary check, squashed and merged at b9ba62507dd2e6fa6937efbfd9353c7d3922916f